1. Technical Field
The present invention relates to an electro-optic device such as a liquid crystal device, a method of manufacturing the electro-optical device, and an electronic apparatus such as a liquid crystal projector including the electro-optic device.
2. Related Art
Such an electro-optic device includes pixel electrodes, scanning lines and data lines used to selectively drive the pixel electrodes, and TFTs (Thin Film Transistor) as pixel switching elements on a substrate. In addition, the electro-optic device is configured to enable active-matrix driving. On the substrate, a laminated structure in which various functional films such as a conductive film or a semiconductor film forming the scanning lines, the data lines, the TFTs, and the like are laminated are formed in each of pixels. In the laminated structure, pixel electrodes are disposed on the uppermost layer, for example.
The pixel electrodes are generally formed of an ITO (Indium Tin Oxide) film and electrically connected to a conductive film formed of, for example, aluminum and disposed in a lower layer through contact holes formed in an interlayer insulating film. In this case, when the pixel electrodes formed of, for example, an ITO film and the conductive film formed of, for example, aluminum are directly connected to each other, electrolytic corrosion, which is a phenomenon occurring when the pixel electrodes formed of an ITO film and the like turn dark, may occur in the pixel electrodes formed of, for example, an ITO film since current flows between the pixel electrodes and the conductive film due to an alkaline removing liquid used in a patterning process of a manufacture process.
In order to solve the problem, JP-A-2005-242296 discloses a technique for preventing the above-described electrolytic corrosion by providing an electrolytic corrosion preventing film formed of, for example, titanium nitride between the pixel electrodes and the conductive film in a laminated structure. In addition, JP-A-2005-242296 discloses a technique for suppressing heat generation caused due to a high light-absorbing ratio of the electrolytic corrosion preventing film formed of, for example, titanium nitride, by providing the electrolytic corrosion preventing film formed of, for example, titanium nitride only in a region where the pixel electrodes on the conductive film and the contact holes for connecting the conductive film are formed.
However, in the technique disclosed in JP-A-2005-242296, the electrolytic corrosion preventing film formed of, for example, titanium nitride has to be subjected to a patterning process by, for example, etching the conductive film formed of, for example, aluminum. At this time, when an etching selection ratio between the electrolytic corrosion preventing film and the conductive film during the etching is low, the etching selection ratio has to be increased by using a mixed gas of carbon fluoride and oxygen. However, when the mixed gas of carbon fluoride and oxygen is used, an isotropic etching process has to be performed on the electrolytic corrosion preventing film. Accordingly, it is difficult to perform a precise patterning process on the electrolytic corrosion preventing film. Therefore, there occurs a technical problem in that the above-mentioned electrolytic corrosion occurs since the electrolytic corrosion preventing film is subjected to an unnecessary etching process and the pixel electrodes and the conductive film are directly connected to each other.